Hi Malcolm - Since storage & sleep privacy are your two main goals with your renovation, the best ideas I spotted in your inspiration links for storage are:

A: Adding stairway storage under your risers:

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B: Adding Japanse Tansu under-stair cabinetry:

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C. Add doors to the space under your loft / beside your stairs and officially turn it back into a storage closet.

As for privacy of your sleeping loft, how about hanging wide black fabric retractable window blinds that you can roll up in the morning and let down at night?

BlindSaver.com has wonderful products:

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BlindSaver Basics Cordless Cellular Shade offers child safe operation and custom quality at a fraction of the cost. The fabric provides excellent UV blockage in a durable non-woven polyester fabric. The dust resistant and washable fabric will not fade or fray. Every shade comes standard with a cordless lift system which is easy to use, child safe and pet safe.

Cordless Lift standard on every shade for pet and child safe operation.
Control handle on the bottom rail. Keeps fingers off of the fabric.
Integrated bracket and head rail system for a seamless appearance and easy installation.
The fabric is non-woven polyester and is dust resistant and has a washable surface.
Plus it will not fade or fray.
The 1/2 inch single cell fabric is versatile and looks great in almost any window size.
Backed by our Limited-Lifetime Warranty.